BackForwardInstrument:  IR spectrometer 

Instrument details
Acronym IR spectrometer
Full name Infra Red Spectrometer
Purpose Benchmark data for climate monitoring: extended spectrum towards Space
Short description Range 5-50 μm, spectral resolution 0.5 cm-1. radiometric accuracy 0.1 K at 300 K nadir-pointing, IFOV 100 km.
Background New development
Scanning Technique Nadir only
Resolution 100 km
Coverage / Cycle Global coverage in 1 month for 100 km average spacing
Mass Power Data Rate

 

Providing Agency NASA
Instrument Maturity Backed by strong heritage
Utilization Period: TBD
Last update: 2022-11-28
Detailed characteristics
Satellites this instrument is flying on

Note: a red tag indicates satellites no longer operational, a green tag indicates operational satellites, a blue tag indicates future satellites

Instrument classification
  • Earth observation instrument
  • Passive optical radiometer or spectrometer
  • Cross-nadir infrared sounder, possibly including VIS channels
WIGOS Subcomponents
  • Subcomponent 1
  • Absolutely calibrated broadband radiometers, and TSI and SSI radiometers
  • Broadband radiometer (for ERB)
  • On-orbit measurement reference standards for VIS/NIR, IR, MW absolute calibration.
  • On-orbit measurement reference standards for VIS/NIR, IR, MW absolute calibration.
Mission objectives
Primary mission objectives
  • Atmospheric temperature
  • Height of the top of PBL
  • Height of the tropopause
  • Integrated Water Vapour (IWV)
  • Sea surface temperature
  • Specific humidity
  • Temperature of the tropopause
  • Upward long-wave irradiance at TOA
  • Upward spectral radiance at TOA
Evaluation of Measurements

The following list indicates which measurements can typically be retrieved from this category of instrument. To see a full Gap Analysis by Variable, click on the respective variable.

Note: table can be sorted by clicking on the column headers
Note: * Primary mission objective.
VariableRelevance for measuring this variableOperational limitationsExplanation
Atmospheric temperature*2 - very highCloud sensitive.. Inaccurate in low troposphere.. Along-track only.TIR spectrometry in the 15 micrometer band
C2H23 - highCloud sensitive.. Coarse vertical resolution.. Along-track only.TIR spectrometry. C2H2 lines around 7.5 and 13.7 micrometers
C2H63 - highCloud sensitive.. Coarse vertical resolution.. Along-track only.TIR spectrometry. C2H6 lines around 12 micrometers
CFC-113 - highCloud sensitive.. Coarse vertical resolution.. Along-track only.TIR spectrometry. CFC-11 lines around 9.2 and 11.7 micrometers
CFC-123 - highCloud sensitive.. Coarse vertical resolution.. Along-track only.TIR spectrometry. CFC-12 lines around 8.8 and 10.8 micrometers
CH4 mole fraction3 - highCloud sensitive.. Coarse vertical resolution.. Along-track only.TIR spectrometry. CH4 lines around 7.7 micrometers
ClONO22 - very highCloud sensitive.. Coarse vertical resolution.. Along-track only.MWIR and TIR spectrometry. ClONO2 lines around 5.7, 7.7 and 12.5 micrometers
Cloud cover5 - marginalDiscontinuous coverage.. Along-track only.TIR channel(s)
Cloud ice2 - very highAlong-track only.Cirrus clouds observed in the UT/LS by FIR spectrometry
Cloud ice Total Column3 - highAlong-track only.Cirrus clouds observed in the UT/LS by FIR spectrometry
Cloud ice effective radius2 - very highAlong-track only.Cirrus clouds observed in the UT/LS by FIR spectrometry
Cloud top height2 - very highDiscontinuous coverage.. Along-track only.MWIR and TIR spectrometry in window and water vapour band (for emissivity) to estimate cloud top height from its temperature
Cloud top temperature1 - primaryDiscontinuous coverage.. Along-track only.TIR spectrometry in window and water vapour band (for emissivity)
CO2 mole fraction3 - highCloud sensitive.. Coarse vertical resolution.. Along-track only.TIR spectrometry. CO2 lines around 15 micrometers
COS3 - highCloud sensitive.. Coarse vertical resolution.. Along-track only.TIR spectrometry. COS lines around 11.6 micrometers
Downward long-wave irradiance at Earth surface2 - very highCloud sensitive.. Highly indirect.. Along-track only.MWIR and TIR spectrometry including water vapour and CO2 bands
H2O1 - primaryCloud sensitive.. Along-track only.Spectrometry in MWIR/TIR in a range centred on 6.3 micrometers; and FIR in a range centred on 18 micrometers
Height of the top of PBL*5 - marginalCloud sensitive.. Along-track only.TIR spectrometry. Height of PBL top from temperature profile
Height of the tropopause*5 - marginalCloud sensitive.. Along-track only.TIR spectrometry. Height of tropopause from temperature profile
HNO33 - highCloud sensitive.. Coarse vertical resolution.. Along-track only.MWIR and TIR spectrometry. HNO3 lines around 5.9, 7.6 and 11.3 micrometers
Land surface temperature4 - fairCloud sensitive.. Coarse spatial resolution.. Along-track only.TIR spectrometry (inclusive of several narrow-bandwidth windows and absorption bands for atmospheric corrections)
Long-wave Earth surface emissivity2 - very highCloud sensitive.. Long time series needed.. Along-track only.MWIR and TIR spectrometry measuring land temperature in many windows. Emissivity inferred by statistical analysis
N2O mole fraction3 - highCloud sensitive.. Coarse vertical resolution.. Along-track only.TIR spectrometry. N2O lines around 7.7 micrometers
N2O53 - highCloud sensitive.. Coarse vertical resolution.. Along-track only.MWIR and TIR spectrometry. N2O5 lines around 5.8 and 8 micrometers
NO3 - highCloud sensitive.. Coarse vertical resolution.. Along-track only.MWIR spectrometry. NO lines around 5.3 micrometers
NO23 - highCloud sensitive.. Coarse vertical resolution.. Along-track only.TIR spectrometry. NO2 lines around 6.1 micrometers
NO2 Total Column4 - fairCloud sensitive.. Along-track only.TIR spectrometry. NO2 lines around 6.1 micrometers
O33 - highCloud sensitive.. Coarse vertical resolution.. Along-track only.TIR spectrometry. Ozone band around 9.7 micrometers
O3 Total Column3 - highCloud sensitive.. Along-track only.TIR channel(s). Ozone lines in band around 9.7 micrometers
PAN3 - highCloud sensitive.. Coarse spatial resolution.. Along-track only.MWIR and TIR spectrometry. PAN lines around 5.7, 8.6 and 12.5 micrometers
PSC occurrence2 - very highCoarse vertical resolution.. Along-track only.MWIR and TIR spectroscopy
Sea surface temperature*3 - highCloud sensitive.. Along-track only.TIR spectrometry (inclusive of several narrow-bandwidth windows and absorption bands for atmospheric corrections)
SF63 - highCloud sensitive.. Coarse vertical resolution.. Along-track only.TIR spectrometry. SF6 lines around 10.5 micrometers
SO22 - very highCloud sensitive.. Coarse vertical resolution.. Along-track only.TIR spectrometry. SO2 lines around 7.3 and 8.6 micrometers
SO2 Total Column2 - very highCloud sensitive.. Along-track only.TIR spectrometry. SO2 lines around 7.3 and 8.6 micrometers
Specific humidity*1 - primaryCloud sensitive.. Along-track only.TIR and FIR spectrometry in bands around 6.3 and 18 micrometers
Integrated Water Vapour (IWV)*1 - primaryCloud sensitive.. Along-track only.TIR and FIR spectrometry in bands around 6.3 and 18 micrometers
Temperature of the tropopause*4 - fairCloud sensitive.. Along-track only.TIR spectrometry. Tropopause temperature from temperature profile
Upward spectral radiance at TOA*1 - primaryMissing all Short-waves and MWIR.. Along-track only.TIR and FIR spectrometry resolving water vapour lines in the bands around 6.3 micrometers and 18 micrometers
Upward long-wave irradiance at TOA*3 - highSpectral interpolation needed.. Along-track only.TIR and FIR spectrometry in the 11 micrometers window region, and in water vapour and CO2 bands around 6.3, 15 and 18 micrometers
Upward long-wave irradiance at Earth surface2 - very highCloud sensitive.. Highly indirect.. Along-track only.TIR spectrometry covering the 11 micrometers window region and the water vapour and CO2 bands around 6.3 and 15 micrometers